diff --git a/backstage/application/api/controllers/api/Applet.php b/backstage/application/api/controllers/api/Applet.php
index 99f8aaa..6057c46 100644
--- a/backstage/application/api/controllers/api/Applet.php
+++ b/backstage/application/api/controllers/api/Applet.php
@@ -193,6 +193,9 @@ class Applet extends REST_Controller {
         }
         $applet_openid = $this->input->post("applet_openid", true);
 
+        // 先清空关于这个openid的数据
+        $this->User_model->clearAppletOpenid($applet_openid);
+
         $res = $this->User_model->update_user(array('applet_openid' => $applet_openid), $user_id);
         if($res){
             $this->response(array(
diff --git a/backstage/application/api/models/User_model.php b/backstage/application/api/models/User_model.php
index 73b0f74..e1d51d8 100644
--- a/backstage/application/api/models/User_model.php
+++ b/backstage/application/api/models/User_model.php
@@ -1174,4 +1174,11 @@ class User_model extends CI_Model
         $rs = $this->db->query($sql)->result_array();
         return $rs[0];
     }
+
+    // 清空指定applet_openid
+    public function clearAppletOpenid($openid){
+        $this->db->where('applet_openid', $openid);
+        $data = array('applet_openid' => '');
+        return $this->db->update('tb_user', $data);
+    }
 }